a. Field of the Invention
This invention relates to improvements in pneumatic conveyors, and more particularly conveyors of the type used for transporting particulate matter, such as seed, from a bulk storage facility to a planter, drill or similar planting apparatus.
b. Description of Related Prior Art
The recent economic environment has had a dramatic effect on farmers. Minimizing labor-intensive activities and maximizing productivity has become a crucial element for survival in the farming industry.
During planting season, loading seeds into a planter or drill has always been a very labor-intensive operation. One common method for loading a planter or drill is to manually haul or dump seed contained in fifty-pound bags into seed boxes located on the planting apparatus. On each refill, a farmer will carry several bags from his pickup truck, or other storage medium, to the planter or drill. Each bag must be torn open and poured into a seed box. The time consumption and fatigue associated with this manual labor can be very significant and wasteful.
In prior years, this operation was not as much of a problem as it is today because farmers were more typically utilizing two- and four-row planters, and were farming relatively small numbers of acres. In the mechanized agricultural industry of today, however, many farmers utilize twelve- to twenty-four-row (or more) planters and/or large drills that hold forty or more bushels of seed to farm thousands of acres.
Prior art attempts at reducing the time and labor required to fill planters and drills have included providing a large, bulky rotary air lock device connected to a portable seed bin and a pneumatic seed conveyor designed to discharge seeds directly into the planter and drill seed boxes. This system, however, is difficult to handle due primarily to the weight associated with the prior art rotary air lock's metal housing and multi-vane rotor which, as a practical matter, severely limits its portability. These devices generally weigh 400 to 500 pounds. In addition, a ponderous rotary air lock device of this design can cause significant damage to the seed transferred by shearing seeds which become caught between the heavy rotor blades and housing. This, of course, can greatly reduce the seed yield and overall productivity.
Another device aimed at reducing the difficulties of loading planting apparatus with seed is disclosed and claimed in my U.S. Pat. No. 4,846,608, which is incorporated herein by reference. Instead of providing a large, heavy rotary air lock as discussed above, the '608 patent substitutes a venturi unit into a pneumatic seed conveyor connected to a large supply of seeds. The venturi unit causes the seed to be transferred from the seed supply to the pneumatic conveyor by creating a pressure differential and, ultimately, to the planter or drill boxes, as described thoroughly in the '608 patent and therefore omitted here. Although the portability of the venturi unit system represents a significant improvement over a system which includes a large, bulky rotary air lock, operation of the venturi unit system may sometimes encounter problems with unacceptable conveyor line pressure losses and seed clogging, which thereby reduces its seed transfer efficiency.
The present invention as disclosed herein meets the goals attempted by the prior art devices discussed, but does not suffer from the disadvantages mentioned, thereby providing the user of the present invention with the added benefits of greater effectiveness, portability and ease of use.